Yes I have had adverse reactions to herbs and my main suspicion for myself is that my liver was not properly metabolizing the herbs, giving the herbs a much more intense and long-lasting effect than for those who would have a properly-functioning liver. My solution is to use herbs that have a much more gentle effect on the body and are more like foods. Licorice is certainly a very potent herb and should be used with great care, and as you are not aware DGL licorice is much different than regular licorice.